Solar powered Hydroponics

I have only found out about the hydroponics method this month. I plan to set up a farm in Malawi, Africa but one of the challenges will be electricity, which tends to be very unreliable there. I started looking into solar power as an alternative. I see solar powered pumps on-line for sale that seem very cheap and also some people demonstrating the DIY versions though these look to cost more than pre made. Any advice on which route to take? I would be very happy to teach myself and others to build solar panels if it was actually much cheaper.